The invention is generally directed to a device for eradicating insects through the use of electricity. The invention is specifically directed to a device for protecting trees and shrubs from injurious insects by electrocuting the insects as they attempt to climb the trunk of the tree or shrubs.
The control of insects is one of man's oldest problems, particularly in the area of agriculture and in cases where the insects are of the type which transmit disease or are parasites of man.
During modern times, the most affective controls of insects have been through the use of toxic chemicals or insecticides. However, the use of insecticides has had serious side effects, such as the simultaneously killing of beneficial insects such as bees and insects which are predators of other insects. The widespread use of insecticides, particularly in aerial spraying has resulted in the killing of other wild life, such as birds. Also, after prolonged use of the insecticide, the insects which are being controlled develop an immunity to the insecticide.
More recently, efforts have been made to control insects through biological means which do not at the same time harm beneficial insects or other wild life. Examples of such biological controls are the use of bacteria, which affects only the specific insect being controlled, and traps which are provided with olfactory lures. The biological controls are not the complete answer either. The environment is protected; however, not all insects can be controlled in this way and, in many cases, the control is not completely effective.
Some species of insects have resisted all attempts to control them. One of the most troublesome is the caterpillar, particularly the gypsy moth species which has recently completely defoliating millions of acres of forest in the northeast section of the United States. The gypsy moth caterpillar has been attacked on all fronts. While in the egg stage, the eggs, which are layed in masses, are scraped off the tree, or dabbed with a toxic penetrating agent, such as creosote. When the caterpillars are in the first larval stages, they are susceptible to a lethal intestional bacteria which is applied in a spray. At a later stage, the caterpillar is no longer affected by the bacteria and a variety of toxic chemicals are used, which although is effective, it is not effective enough to completely control the caterpillars and at the same time, results in the killing of other wildlife.
The last of defense against the ravages of the caterpillars involves the efforts of individual home owners to save individual trees.
One of the most common methods of protecting an individual tree from caterpillars is the application of a band of sticky tape or metal foil with a sticky substance attached thereto around the circumference of the tree. Eventually, so many caterpillars become entangled in the sticky substance that other caterpillars can then climb over them and proceed up the tree. Also, if the caterpillars are frustrated in their attempt to go up the tree, they may descend and proceed to another tree.
Insect exterminators have also been developed which utilize electric power as the killing agent. The electrical exterminator is essentially a trap having an electrode grid surrounding an insect attracting element, such as a light. As the insects attempt to reach the light, they encounter the electrodes which shorts out through the insects body, thereby electrocuting the insect. The voltage and current is sufficiently high, so that in killing the insect, the body is substantially burned, and in some cases totally obliterated. So much power is used to operate the device, light for attracting and charge for electrocuting the insect, that the device can only be used by utilizing conventional house current. The use of a storage battery would be totally impractical. Also, the voltage and current are sufficiently high to cause a hazzard for anyone touching the electrode grid, so that a protective cage is provided about the electrode grid. The electrical insect exterminators are limited to flying insects which would include gypsy moths as well as the moths of other caterpillars or larval insects which turn into flying insects. However, these devices are ineffective to protect an individual tree or other structure from a crawling insect, such as a caterpillar. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide an insect exterminator which is highly effective for killing all insects which attempt to ascend or descend a structure to which the exterminator is applied.
Another object of this invention is the provision of an insect exterminator which prevents accumulation of dead insects that might otherwise impair the effectiveness of the exterminator.
A further object of the present invention is the provision of an insect exterminator which kills insects through the use of electricity and which prevents crawling insects from ascending or descending a structure.
It is another object of the instant invention to provide an insect exterminator which uses electricity as the killing agent in a manner which is not harmful to humans or pets that may accidentally come into contact with the exterminator.
A still further object of the invention is the provision of an insect exterminator which uses electricity as the killing agent in a manner which utilizes the electrical power efficiently to allow a storage battery to be used as the source of electrical power.
It is a further object of the invention to provide a insect exterminator which uses electrical power from a storage battery in which the low voltage of the storage battery is transformed and pulsed to a high voltage spark which is sufficient to kill the insect without wasting electrical power to obliterate the insects body.
It is a further object of the invention to provide an insect exterminator which includes spaced bands of electrodes attached to a base sheet of insulating material which surrounds the structure to be protected and means for creating a high voltage spark across the electrodes only when an insect attempts to cross the electrodes by utilizing the insects body as a conductor to draw the spark.
It is a further object of the invention to provide an insect exterminator which is easy to install and which is capable of a long life of useful service with a minimum of maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.